osComMarket

fastest way is to generate a CVS via your desktop and load that into your shop.

Despite that it looks good, it is not written good enough. You still use nested tables what is a no-go. You embed forms inside a table what is also a no-go. But i respect the work done. You should take a look at Henry's BS4 admin: https://github.com/osc2nuke/oscommerce-2.3.4.1-CE

i think the moment when it was released "Custom Product Builder", i was one of the first who tried it. 15+ years later...............Not even looked into the code or remember anything. The contribution NOT will go follow your expectations. The dev started with a guy who wanted to sell "desktop computers". Back in that time, it was much easier to tell what was possible and what was not ( in relation to a desktop pc) The add-on never evolved to be used with "any" kind of product. Yet............ it is (still) a very interesting concept. The economy just made it cheaper to buy pre-fabricated items in the meantime. You will go work on an unfinished add-on. Lots of changes required.

Start use: http://kenwheeler.github.io/slick/ All the rest becomes not-necessary, and is easy to code upon-on.

No honey pot need, use google. They covered the issue.